Ammunition hoist



July 9, 1946. R. TWEEDALE AMMUNITION HOIS'I' Original Filed Oct. 3, 1936 5 Sheets-Sheet 2 E L A D E E w T L R AMMUNITION HOIST INVENTOR y 14. R. L. TWEEDALE AMMUNITION HOIST Original Filed Oct. 3, 1936 5 Sheets-Sheet 4 INVENTOR 5y 146. R. TWEEDALE 2,403,886

AMMUNITION HOIST Original Filed Oct. 3, 1936 5 Sheets-Sheet 5 INVENTOR Patented July 9, 1946 AMlVIUNITION HOIST Ralph L. Tweedale, Waterbury, Conn, assignor to The Waterbury Tool Company, Waterbury, Conn., a corporation of Connecticut Application October 3, 1936, Serial No. 103,898 Renewed October 28, 1939 14 Claims.

This invention relates to power transmissions and more particularly to a conveyor for deliver- :ng articles from one station to another wherein a fire hazard is present at one station and in which it is desired to prevent the possibility of flame transmission between the two stations at all times, while permitting the continued passage of articles between the stations. The invention is particularly adapted to delivering ammunition aboard ship from an ammunition storage compartment to a position at the guns for use therein, although it will be understood that the invention may be adapted to other uses wherein similar conditions and problems are encountered.

It is customary in war vessels to locate the ammunition magazines or storage chambers in the lower part of the ship where the possibility of their contents being exploded by enemy projectileS is most remote. The guns which use the ammunition being situated on the upper decks of the ship. either in turrets or on deck mountings, it is necessary to provide means for conveying ammunition from the magazine to a position near the guns where it may be readily placed in the guns as needed.

Various types of conveyors have been heretofore provided for this purpose and where high rates of delivery to rapid firing guns are required, the so-called dredger type ammunition hoists have marked advantages over other types in use. Such a hoist usually comprises an endless chain conveyor which is encased in a continuous tubular hoist trunk or casing extending through the ship from the loading station in or adjacent the magazine to the unloading station adjacent the gun. This continuous hoist trunk provides a conduit which introduces the possibility of flame transmission to the magazine whenever accidental explosions occur at the gun or whenever an enemy projectile explodes in or near the hoist trunk.

In order to break this continuous path for flame travel to the magazine, it has been found necessary heretofore to deliver the ammunition in two stages by two entirely independent ammunition hoists with a transfer station where the ammunition is carried manually from the delivery end of the lower hoist to the loading end of the upper hoist. This construction, while satisfactory from the standpoint of safety of the installation and effectiveness to prevent the transmission of flare-backs to the magazine, adds considerably to the weight and cost of the installation since each of the two sections of the hoist must be provided with its own independent drive mechanism. Furthermore additional crew is re- 2 quired for handling ammunition at the transfer station, which not only increases the number of men required for each gun to be fired but'presents also a retarding element in the delivery of ammunition since'it introduces one more place for unavoidable human errors and delays to interfere with the intended operation of the hoist.

It is an object of the present invention to provide a conveyor particularly adapted for delivery of ammunition directly between a loading station adjacent the magazine and an unloading. station adjacent the gun by which ammunition may be delivered through a continuous closed casing whereby transmission of flare-backs to the'loading station may be prevented without requiring an intermediate transfer station. 7 D

It is also an object to provide a conveyor, for delivering articles between two stations which are separated by a flame-proof wall having an opening at one station adjacent the conveyor and in which is incorporated means for passing articles 7 through the opening while maintaining a flameproof seal at all times.

A further object is to provide a loading station fora conveyor having an article passing mech anism which is actuated by a separate motor means independent of the conveyor drive mechanism.

It is also an object to provide a loading station for a conveyor in which a reciprocatingarticle passing member "is mounted adjacent a wall opening and is provided with at least one article receiving recess adapted to be alternately brought into register with the opening for receiving an article and moved to a position where the article may be transferred to the conveyor.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred form of the present invention is clearly shown.

In the drawings:

Fig. 1 is a diagrammatic ship incorporating a preferred form of the present' invention.

Fig. 2 is a front view of a loading station incorporating the present invention.

Fig. 3 is a fragmentary cross section onlline 33 of Fig. 4.

Fig, 4 is a cross section on line 4-4 of .Fig. 3.

Fig. 5 is a diagrammatic view showing the hydraulic circuits incorporated in the conveyor drive and control mechanism.

Referring now to Fig. 1 there is indicated diagrammatically a portion of a longitudinal section cross section of a of a war vessel having superimposed decks In of usual construction, the spaces between which are divided by partitions I2 into suitable compartments. Indicated at M is a deck gun and at [6 a revolving turret having two or more guns I8 mounted thereon in the usual fashion. Adjacent the gun I4 is mounted the delivery head 29 of a dredger type ammunition hoist 2| having a trunk 22 extending downwardly through the vessel to a compartment 24 which may be either a magazine compartment for the storage of ammunition or a handling room adjacent such a compartment and in whichis located the loading end 25 of the hoist 2! together with suitable driving mechanism for the hoist. In the turret I6 is mounted a delivery head 26 of a second dredger type ammunition hoist 21 having a trunk 28 extending vertically downward to a compartment 30 similar to the compartment 24, in which is located the loading end 32 and the necessary driving mechanism for the hoist 27. The hoist trunk 28 is shown secured to the top deck If! at the center of rotation of the turret I 6 and is stationary relative to the turret although it will be understood that the ammunition hoist 2'! may be mounted to revolve with the turret i6 if desired.

Referring now to Figs. 2 through 5 wherein the construction of the loading ends 25 and 32 is illustrated in detail, there is shown a casing 34 forming the lower end of the hoist trunk to which the casing 34 may be tightly sealed at the flange 36. The casing 34 serves not only to enclose the drive sprockets 49 and the hoist chain or conveyor band 38, having conveyor lugs 39, but also as a mounting for the hoist driving and control mechanism. The latter may be of any suitable construction. The form of drive mechanism and control therefor illustrated comprises a fluid motor 42 adapted to drive the sprockets through a worm drive 44. A variable displacement pump 46 (see Fig. 5) and auxiliary pump 48 are driven by an electric motor 50 to supply fluid to the motor 42 through .a control unit 52. The control unit 52 is constructed to control the displacement of the pump 46 and to control communication between the pump 46 and the motor 42 through conduits 54 in a manner to provide for automatically moving the hoist chain 38 through one flight whenever a starting shot of fluid from the auxiliary pump 48 is admitted to the device 52 through a control conduit 56.

For this purpose the control unit 52 comprises a body 4| having a cylindrical bore 43 in which is mounted a spool valve 45 for the purpose of blocking or opening the passage of oil between the conduits 54 and conduits 41. A second cylindrical chamber 49 carries a spool valve 5! for the purpose of reversing the flow between the conduits 41 and a pair of conduits 53 which lead to the fluid motor 42. The body 4| also has at its upper end a bore 55 in which is mounted a spool valve 51 for controlling the stroke regulating fluid motor of the pump 46. A conduit 59 extends from the auxiliary pump 48 to the upper end of the bore 55 while a conduit 60' enters the bore 55 at its mid-portion. The valve 51 is adapted to selectively control and reverse the connections of the conduits 59 and 60' with a pair of conduits '63 and leading to opposite ends of the stroke regulating mechanism at the pump 46. The valves 45 and 5! are formed integrally upon a common stern having an enlarged portion 61 around which is slidably mounted a lift piston 69.

The latter has a cylindrical upper portion 4 H slidably fitted in a chamber 13 which communicates with the upper end of the bore 55 through a passage 15 formed in the spool of valve 51. The piston 69 has a portion I6 of larger diameter than the portion H and slidably fitted in a chamber 18' to which the conduit 56 leads. The bottom wall of the piston 69 is provided with an opening forming a clear passage around the stem of valve 45 and having a seat on which the enlarged portion 61 of the stem is adapted to rest for the purpose of closing this passage. The space inside the piston 16' communicates with the tank through va passage formed in the stem of the valve 45. At its lower end the valve stem has a roller 82' acting as a follower for a cam 85. The latter is connected by a suitable drive means not shown to the shaft of the sprockets 49 50 that the cam makes one revolution while the chain 38 travels through one night distance. The cam 85 has a depression in which the roller 82 is shown at rest. In this position the valve 45 is completely closed while the valve 51 connects the conduit 63 to the pressure line 59 and the conduit 65 to the tank line 60'. To either ide of this depression are elevated portions 81 which hold the valves in such a position that the valve 45 is opened to a. considerable degree while the valve 51 still connects conduit 63 with the conduit 59 and conduit 65 with conduit 60'. The remainder of the periphery of the cam 85 is raised still further so as to completel open the valve 45 and to reverse the connections at the valve 51. When the valves are raised to this upper extreme position the valve stem has been lifted higher than it is possible to lift the piston 69, so that the enlarged portion 61 lifts away from the seat in the bottom wall of the piston 69. The cam 85 and its drive mechanism are enclosed in a suitable oil-tight housing not shown, the interior of which is connected to tank.

The entire arrangement of the control unit 52 is such that whenever a shot of oil is admitted through the conduit 56 to the chamber 18', the piston 69 is lifted due to the enlarged portion 6'! being on its seat in the bottom wall of the piston 69. The piston69 and both valves 45 and 51 are accordingly lifted to a position just short of the highest position to which the cam would lift them. Thus the valve 45 is opened and the valve 51 is reversed to cause the stroke of the pump 46 to be increased at a rate determined'by the volumetric capacity of the auxiliary pump 48. Oil is delivered to and returned from the fluid motor 42 through the conduits 54, [Land 53, thus causing the motor 42 to operate, turning the cam 85. The latter will contact the roller 82' after about one-quarter of a revolution when the highest part of the cam strikes the roller 82', thus lifting the valves 45 and 5! a further amount. This additional lift raises the enlarged portion 61 off from the seat in the bottom wall of the piston 69, thus permitting the oil trapped in the chamber 18' to escape through the opening in the bottom wall of the piston 69 and through the passage 8| to tank. As soon as the cam has completed an approximate one-half revolution in addition, the roller 82' drops down to the cam'portion 81, thus reversing connections at valve 51 but not completely closing the valve 45. The stroke of the pump '46 is thus reduced at.a rate determined by the capacity of pump 48 causing the motor 42 to decelerate. When the cam 85 has completed a revolution, the roller 82' returns to the position shown in the drawings, completely closing the valve 45. At this time the enlarged portion 61 again comes to rest on its seat in the bottom wall of piston 69, thus placing the apparatus in condition for restarting whenever another shot of oil is introduced to the conduit 56. It will be noted that should a shot of oil be introduced to the conduit 58 before the cam 85 has made one revolution, the lift piston 69 will not rise because a free path is opened from the chamber I8 to tank through the passage in which the enlarged portion 61 seats. It will also be noted that oil pressure from the auxiliary pump is constantly exerted over the upper end of the valve 5'! creating a bias for the entire stem assembly in the downward direction. Likewise this pressure is exerted over the annular area at the top of the portion II of the lift piston 69 biasing the latter downwardly whenever pressure is relieved in the chamber I8 by the opening of the passage through the bottom wall of the piston 19.

The casing 34 is provided on its front face with an outward extension 58 having a pair of openings 60 and BI of proper size and shape to permit a piece of ammunition to pass therethrough. The extension 58 is hinged to the casing 34 at 62 along one edge thereof and is adapted to be clamped in sealing engagement therewith by suitable securing means 64. The extension 58 is formed with a chamber 66 in which is mounted a reciprocating carrier member 68 which forms a pair of adjacent recesses and I2. For this purpose the carrier 68 is formed with a bottom wall I4 and a, similar top wall, not shown, and with three vertical walls I6 forming the sides of the chambers I0 and 12. The width of the chambers I0 and I2 and the spacing of the openlugs 60 and 6| are such that the carrier 68 may be reciprocated between the position shown in Fig. 4 in which the recess I0 is opposite the opening 60 and a position to the left thereof in which the recess I2 is opposite and in register with the opening 6 I.

Intermediate the openings 60 and 6| in the back wall of the chamber 66 is formed an opening 18 opposite the hoist chain 38 and with which either of the recesses I0 and 12 may register when the other is in register with an opening 60 or 6|. A pair of flapper doors 1! are pivoted in the casing 34 at the sides of the opening I8 and are spring biased to closed position and adapted to be opened at certain times by trip levers I9 lying in the path of lugs 39. Bevel gearing 8| connects the trip levers I9 to the pivot shafts of the flapper doors IT. A lost motion drive connection at 83 permits the trip levers 19 to be moved downwardly without actuating the doors I1 during lowering operation of the hoist.

In front of the carrier 68 there is reciprocably mounted a sliding door 80 of proper width to close one of the openings 60 or 6| while leaving the other open. The carrier 68 and the door 80 each carry rigidly secured thereto downwardly extending pins 82 and 84 respectively which project through slots 86 and 88 formed in the bottom wall 90 of the extension 58. A lever 92 is pivoted to the wall 90 on the lower side thereof embracing at its outer ends the pins 82 and 84 whereby the carrier 68 and the door 80 are caused to move simultaneously in opposite directions. The pin 82 extends below the lever 92 to enter a bore formed in an operating piston 94 which is re ciprocably mounted in a pair of cylinders 96. The cylinders 96 are formed integrally with a cover plate 98 which is removably secured to the bottom wall 90 to cover the mechanism attached thereto. Also formed integrally in the cover 98 are a pair of directional control valves I00 and I02. The movable elements of valves I00 and I02 are mounted on a common stem I04 which is connected by a fork and collar connectionto a snap action lever I06. The latter is pivotedcoaxially'with the lever 92 and connected to be operated thereby through a spring I08 to provide snap movement of the lever I06 as the lever 92 reaches either end of its oscillation.

Mounted on the casing 34 behind a back wall IIO of the chamber 66 are a pair of carrier trip valves H2 and H4. Each of these valvesisconnected for operation by a trip lever H6 and H8, respectively, each of which has a portion projecting into the chamber 66 and into the recesses I0 and 12 when opposite one of the openings 60 and BI. The trip levers H6 and H8 are adapted to be moved counterclockwise in Fig. 3 whenever a piece of ammunition is properly placed in a recess I0 or 12. Pivotally mounted in the casing 34 adjacent the lower edgeof the opening I8 at I20 is a lower trip lever I22 adapted to be depressed by a piece of ammunition'such as I24 when it is placed in position on the hoist chain 38. The lower trip'I22 is connected by an arm I26 (see Fig. 5) ton, lower trip valve I28 mounted'in a valve block I30. 'An upper trip valve I32 is also mountedin the block I30 and is adapted to be actuated by solenoid I34 which in turn is controlled by an upper trip I36 located at the delivery end of the hoist;

The valve I28 is adapted to connect a conduit I38 with a conduit I40 when the trip I22 is depressed and to connect with a conduit I42 when the trip I22 is raised. The valve I32 is adapted to open communication between the conduit I40 and the conduit 56 whenever the solenoid I34 is energized and to close communication when the solenoid is deenergized. The solenoid I34 isunder the control of the upper trip I36 through a three-way switch I44 which is connected in circult with a, three-way switch I46 adapted to be actuated by a reversing lever I48. When the reversing lever I48 is set to hoist ammunition, as illustrated in Fig. 5, the switch I46 connects the solenoid to the switch I44 so that the solenoid will be energized from the source I 45 whenever the trip I36 is released by removal of ammunition from the delivery end of the hoist. With 'the reverse lever I48 set for lowering ammunition, the switch I46 connects theswitch I44 for opposite action.

The lever I48 also controls a reversing valve trip valve I28 admits fluid to the conduit I48,

For this purpose a conduit I82 extends from the conduit I40 to the left-hand end of the relay valve I58 for admitting pressure fluid to the end surface of a large piston I64. The large piston I84 is connected by a stem I66 to a small piston I68, the space to the right of which is connected to the expansion tank I70 through 'a conduit I12.

The large piston I 64 when in the position illus- I trated blocks communication between conduits .7 I60 and I56. When the piston I64 moves to the left due to the release of pressure fluid in the conduit I49, communication is established between the auxiliary pump 48 and the carrier trip valves H2 and II4 through conduits I52, I59, and I56. Each of the valves H2 and H4 comprise a piston valve I14 adapted to open communication between the conduit I56 and a conduit I16 leading to the corresponding directional control valve I99 or I02, whenever the trip lever H6 or H8 is depressed by a piece of ammunition lying in one of the recesses 19 or 12. .A pressure operated holding valve I18 is also mounted in each valve block H2 and H4 and is moved to the right in Fig. Whenever fluid pressure is admitted through the valve I14 to the conduit I16. This movement opens communication between the conduit I16 and conduit I56 through a parallel path including a restrictive conduit I39 so that when fluid pressure is once admitted to the conduit I16 by the opening of valve I14, the pressure is maintained therein through the .valve I18 so long as there is any existing back pressure at the remote end of the conduit I16. The valves I09 and I62 are adapted to selectively connect a cylinder 96 either with a conduit I16, as shown in Fig. 5, or to connect both a cylinder 96 and a conduit I16 with the expansion tank I10 through a branch I92 of the conduit I12. In operation with the motor 59 and pumps 48 and 48 running and with the hoist at rest due to the presence of a piece of ammunition at the delivery station, the trip I36 keeps the solenoid I34 deenergized so that fluid from the pump 48 is blocked off from the conduit 56 at the valve I32. Assuming a piece of ammunition to have been dropped from the recess 12 by the flapper doors 11 and to lie on the chain 38 and the lower trip I22, as illustrated in Fig. 5, as soon as the ammunition is removed from the delivery station trip I36 is released to energize solenoid I34, opening valve I32 to admit pressure fluid to the conduit 56. The control unit 52 in response to the admission of pressure fluid to the conduit 56 causes the fluid motor 42 to drive the sprockets 40 and chain 38 through one flight; that is, through the distance to bring the next lug 39 into rest position, as illustrated in Fig. 5.

Assuming a piece of ammunition to have been placed in the recess 10 through the opening 611 before the start of the hoist cycle, the trip H6 will be depressed so that valve I14 will be open. With the piston 94 and the valve IUD lying in the position illustrated in Fig. 5, the piston 94 will not be actuated at the beginning of the cycle until the lug 39 has picked the ammunition off from the lower trip I22 and permitted the latter to raise, thus transferring the conduit I49 from the pressure line I39 to the drain line I42. As soon as this occurs the lower trip relay valve I58 moves to the left admitting pressure fluid from the conduit ISO to the conduit I 56. The piston 94 is thereby caused to move to the left in Fig. 5 moving the carrier 66 to the left and through the lever 92 moving the door 80 to the right in Fig. 4. This action once started is continued regardless of the release of trip IIE as the ammunition moves to the left away from the same because the holding valve I13 opens a connection around th valve I14 through the passage I80. When the piston 94 completes. its movement to the left, the recess 10 is opposite the flapper doors 11 and the recess 12 is opposite the opening 6|. Near the end of the flight the next lug 39 actuates the trip levers 19 to open the doors 11 and the ammunition .in the recess 10 accordingly drops on to the chain 38 .and lower tri 22 is ready for the next cycle of operation. At the end of the movement of piston 94 the snap acting lever IE6 is operated to shift the valves Hi9 and I02 connecting the left-hand cylinder 96 to valve H4 and connecting the right-hand cylinder 96 to the drain conduit I82. The holding valve I18 is thereby permitted to move .to the left again closing the by-pass I89 until such time as pressure fluid is again admitted to the conduit I16.

While the form of embodiment of the invention as herein disclosed (constitutes a preferred form, it is to be understood that other forms might be adopted, all .coming within the scope of the claims which follow.

What is claimed is as follows:

1. In a conveyor for delivering ammunition .between a loading station adjacent a storage .compartment and a station for use and .having an endless flexible ammunition conveyor band, a flame-proof casing surrounding the conveyor band and means for driving the conveyor .band, the combination with the conveyor of means for passing ammunition into said casing at the loading station and separate motor means for driving the ammunition passing means, whereby .the ammunition passing means may be operated while the conveyor is stationary.

2. In a conveyor for delivering.ammunitionbetween a loading station adjacent a storage compartment and a station for use and .having an endless flexible ammunition conveyor band, a flame-proof casing surrounding the conveyor band and means for driving the conveyor band, the combination with the conveyor of means for passing ammunition into said casing at the loading station, separate motor means for driving the ammunition passing means, and means responsive to the positioning of a piece of ammunition on the conveyor for controlling operation of said motor.

3. In a conveyor for delivering ammunition -be tween a loading station adjacent a storage compartment and a station for use and having an endless flexible ammunition conveyor band, a flame-proof casing surrounding the conveyor band and means for driving the conveyor band, the combination with the conveyor of .means ,for passing ammunition intosaid casing at the loading station, separate motor means for driving'the ammunition passing means, and means responsive to positioning of a piece of ammunitionin the ammunition passing means for controlling operation of said motor.

4. In a conveyor for delivering ammunitionbetween a loading station adjacent astorage compartment and a station for use and having an endless flexible ammunition conveyor band, a flame-proof casing surrounding the conveyor band and means for driving the conveyor band, the combination with the conveyor of means-for passing ammunition into said casing at the loading station including'a linearly reciprocable carrier having an ammunition'receivingrecess, and. means cooperating with the ammunition passing means for maintaining a flame-proof seal between the inside and outside of the casing at all times whereby the transmission of flare-backs from the use station to the loading station is prevented.

5. In a conveyor for delivering ammunition :between a loading station adjacent a storage compartment and a station for use and having ;an

endless flexible ammunition conveyor band, a flame-proof casing surrounding the conveyor band and means for driving the conveyor band, the combination with the conveyor of means for passing ammunition into said casing at the loading station including a linearly reciprocable carrier having an ammunition receiving recess, means cooperating with the ammunition passing means for maintaining a flame-proof seal between the inside and outside of the casing at all times whereby the transmission of flare-backs from the use station of the loading station is prevented, and separate motor means for driving the ammunition passing means.

6. In a conveyor for delivering ammunition between a loading station adjacent a storage compartment and a station for use and having an endless flexible ammunition conveyor band, a flame-proof casing surrounding the conveyor band and means for driving the conveyor band, the combination with the conveyor of means for passing ammunition into said casing at the loading station, and means including an alternately reversing fluid motor for driving the ammunition passing means.

7. In a conveyor for delivering ammunition between a loading station adjacent a storage compartment and a station for use and having an endless flexible ammunition conveyor band, a flame-proof casing surrounding the conveyor band and means for driving the conveyor band, the combination with the conveyor of means for passing ammunition into said casing at the loading station including a reciprocable carrier having an ammunition receiving recess, means cooperating with the ammunition passing means for maintaining a flame-proof seal between the inside and outside of the casing at all times whereby the transmission of flare-backs from the us station to the loading station is prevented, and means including a reciprocating piston motor for reciprocating said carrier.

8. In a conveyor for delivering articles between two stations the combination of an endless flexible conveyor band, means for driving said conveyor band, means forming a flame-proof wall between said conveyor band and one of said stations, said wall having an opening adjacent the conveyor band through which articles may pass, means associated with said opening for passing articles therethrough and cooperating with said opening for maintaining said opening sealed against the passage of flame, and separate motor means for driving the article passing means.

9. In a conveyor for delivering articles between two stations the combination of an endless flexible conveyor band, means for driving said conveyor band, means forming a flame-proof wall between said conveyor band and one of said stations, said wall having an opening adjacent the conveyor band through which articles may pass, means associated with said opening for passing articles therethrough and cooperating with said opening for maintaining said opening sealed against the passage of flame, separate motor means for driving the article passing means, and means responsive to the positioning of an article on the conveyor for controlling operation of said motor.

10. In a conveyor for delivering articles between two stations the combination of an endless flexible conveyor band, means for driving said conveyor band, means forming a flame-proof wall between said conveyor band and one of said sta tions, said wall having an opening adjacent the conveyor band through which articles may pass, means associated with said opening for passing articles therethrough and cooperating with said opening for maintaining said opening sealed against the passage of flame, separate motor means for driving the article passing means, and means responsive to the positioning of an article in the article passing means for controlling operation of said motor.

11. In a conveyor for delivering articles between two stations the combinationof an endless flexible conveyor band, means for driving said conveyor band, means forming a flame-proof wall between said conveyor band and. one of said stations, said wall having an opening adjacent the conveyor band through which articles may pass, means including a linearly reciprocable carrier having an article receiving recess associated with said opening for passing articles therethrough and cooperating with said opening for maintaining said opening sealed against the passage of flame, and means for driving the article passing means.

12 In a conveyor for delivering articles between two stations the combination of an endless flexible conveyor band, means for driving said conveyor band, means forming a flame-proof wall between said conveyor band and one of said stations, said wall having an opening adjacent the conveyor band through which articles may pass, means associated with said opening for passing articles therethrough and cooperating with said opening for maintaining said opening sealed against the passage of flame, and means including an alternately reversing fluid motor for driving the article passing means.

13. In a conveyor for delivering articles between two stations the combination of an endless flexible conveyor band, means for driving said conveyor band, means forming a flame-proof wall between said conveyor band and one of said stations, said wall having an opening adjacent the conveyor band through which articles may pass, means including a reciprocable carrier having an article receiving recess associated with said opening for passing articles therethrough and cooperating with said opening for maintaining said opening sealed against the passage of flame, means for driving the article passing means, and means including a reciprocating piston motor for reciprocating said carrier.

14. In a conveyor for delivering articles between two stations the combination of an endless flexible conveyor band, means for driving said conveyor band, means forming a flame-proof wall between said conveyor band and one of said stations, said wall having an opening adjacent the conveyor band through which articles may pass, means including a linearly reciprocable carrier having an article receiving recess associated with said opening for passing articles therethrough transversely to the reciprocation of the carrier and cooperating with said opening for maintaining said opening sealed against the passage of flame, and means for driving the article passing means.

RALPH L. TWEEDALE. V

Certificate of Correction Patent No; 2,403,886. July 9, 1946.

RALPH L. TWEEDALE It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows: Column 5, line 19, for piston 79 read piston 69; column 9, line 54, claim 8, after passing means and before the period insert the comma and Words whereby the ammunition passing means may be operated while the conveyor is stationary; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 29th day of October, A. D. 1946.

LESLIE FRAZER,

First Assistant Commissioner of Patents. 

